He Zhanbing, Maurice Jean Luc, Ma Haikun, Wang Yanguo, Li Hua, Zhang Tiantian, Ma Xiuliang, Steurer Walter
State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, People's Republic of China.
LPICM, CNRS, Ecole polytechnique, Institut Polytechnique de Paris, Palaiseau, France.
Acta Crystallogr A Found Adv. 2021 Sep 1;77(Pt 5):355-361. doi: 10.1107/S2053273321007518. Epub 2021 Aug 13.
Quasicrystals have special crystal structures with long-range order, but without translational symmetry. Unexpectedly, carousel-like successive flippings of groups of atoms inside the ∼2 nm decagonal structural subunits of the decagonal quasicrystal AlCrFeSi were directly observed using in situ high-temperature high-resolution transmission electron microscopy imaging. The observed directionally successive phason flips occur mainly clockwise and occasionally anticlockwise. The origin of these directional phason flips is analyzed and discussed.
准晶体具有特殊的晶体结构，具有长程有序性，但没有平移对称性。出乎意料的是，利用原位高温高分辨率透射电子显微镜成像，直接观察到了二十面体准晶体AlCrFeSi的约2纳米二十面体结构亚基内原子团的类似旋转木马的连续翻转。观察到的定向连续相子翻转主要沿顺时针方向发生，偶尔也会沿逆时针方向发生。对这些定向相子翻转的起源进行了分析和讨论。
